The first of two 48-hour strikes by Royal Mail postal workers has taken place.
Royal Mail customers can expect this strike to lead to more delays
Prior to a deal being reached on 12 October, a programme of rolling strikes was scheduled to start on 15 October.
What would this strike action mean for postal services?
Everybody can expect delays, although Royal Mail says that it is prioritising letters that are sent "special delivery".
However, money-back guarantees will be suspended for special delivery items posted from Thursday onwards.
Those waiting for other items of post may simply have to wait. Previous strikes were over 24 hours, but this time there will be two 48-hour walkouts. Delays will be therefore longer.
Royal Mail will not be delivering unaddressed "junk" mail during this period
What is Royal Mail advising for small businesses and residential customers?
Bring your mailing forward to avoid the strike days - Royal Mail will process letters in the order they arrive, so the sooner it is received, the less severe the delay is likely to be.
Do not delay postings until after strike days, as it is likely to take some time to clear the backlog of mail.
I am a small business owner - what could the strike mean for me?
Having regular postal deliveries is particularly important for small businesses.
UK businesses send and receive about 600 million cheques a year, according to the banking industry.
The Federation of Small Businesses (FSB) has said its members suffer particularly badly from such action because they are more likely to rely exclusively on Royal Mail.
"A cheque delayed in the post can mean the difference between life and death for a small business," an FSB spokesman said at the time of the first 24-hour stoppage.
The British Chambers of Commerce says that firms who still rely on cheques may step up their efforts to move to online payments and consider using the services of Royal Mail's rivals.
Is there any insurance I can take out?
Unfortunately, the answer is no.
Payment delays and other costs incurred by a postal dispute are not covered by business interruption insurance, the Association of British Insurers (ABI) told the BBC.
Business interruption insurance is designed to pay out if a business has to shut due to fire, flood or some other mishap.
I have sent a cheque off to my gas supplier to pay a bill. How worried should I be that they will not receive it?
If you fear your bill becoming overdue the best advice is to phone your supplier and explain the situation.
Tell them you have put the cheque in the post but it may be delayed, so that they can then enter the details of your call on your account file.
A British Gas spokeswoman told the BBC: "We will factor in that there is a postal strike but if people are worried they can call us to discuss the matter."
British Gas urged customers who normally pay by cheque to consider using its online payment service to avoid delay.
I am going on holiday in a few weeks and waiting for a passport to be delivered. Will it be delayed?
The good news is that the UK passport service says that there will be no delay in deliveries.
The passport service uses a private company SMS for passport delivery.
SMS will not be on strike.
But documents, such as birth certificates, submitted in support of a passport application are returned to the applicant through the Royal Mail.
As a result, these documents could be delayed.
But there is an option to have your supporting documents returned to you via SMS.
What is the dispute about?
Essentially, it is over pay and potential job cuts.
The Communication Workers' Union (CWU) has rejected a 2.5% pay offer and warned that Royal Mail's modernisation plans will lead to 40,000 job losses.
Postal workers' pay should rise to the national average over the next five years, the union argues, but Royal Mail says this would amount to a 27% increase which it could not afford.
What does Royal Mail say?
Royal Mail says that it has been losing business to its rivals since the postal market was opened to competition, and urgently needs to modernise its business practices.
Since the liberalisation of the UK postal service in 2005, there are now 17 other companies competing against Royal Mail, especially in the more profitable business mail sector.
The Royal Mail says it has already lost 40% of this corporate market to rivals.
In order to compete, it has to modernise, Royal Mail argues, saying failure to do so has already cost it government deals and, recently, an £8m contract with online retailer Amazon.
The company says it is investing £1.2bn in modernisation to ensure it can compete more effectively against its rivals.