I encountered issues retrieving the most recent strike dates directly from the sources. However, I can provide a general overview based on the pattern of past industrial actions and typical strike announcements.

UK Post Office Strikes Overview

Introduction
Postal workers in the UK, primarily represented by the Communication Workers Union (CWU), have been engaged in a series of strikes over disputes concerning pay, working conditions, and the future of the postal service. These strikes have significant implications for businesses, individuals, and the overall postal service delivery across the UK.

Strike Dates and Impact
Typically, strike actions are announced with several days or weeks of notice, allowing customers to prepare for disruptions. The strikes usually occur over multiple days, often including weekends, to maximize the impact. Recent patterns suggest that these strikes can occur intermittently over a few months, with multiple days in each month affected.

For example, in past strike waves, there were up to 19 days of industrial action spread across two months. The strike dates are strategically chosen to disrupt services during critical periods, such as the lead-up to Christmas, when postal services are in high demand.

Effects on Postal Services
On strike days, postal services face significant disruptions. While Royal Mail and other postal services attempt to maintain some level of operation, delays are inevitable. Deliveries, collections, and customer services all experience slowdowns, with priority items often facing delays of several days.

Customers are advised to avoid posting items close to strike days if timely delivery is critical. Post offices may remain open during strikes, but with limited staffing and services. This results in longer queues and extended waiting times for customers seeking postal services on strike days.

Why Are Postal Workers Striking?
The primary reasons for the strikes are disputes over pay and working conditions. Postal workers have expressed concerns over inadequate pay increases amidst rising living costs and inflation. Additionally, there are concerns about job security, as automation and changes in the postal industry threaten traditional roles within the service.

Workers are also demanding better working conditions, as the current workloads have become increasingly unmanageable due to staff shortages and increased parcel volumes. The union argues that these factors, combined with inadequate pay, make the current situation unsustainable for many postal workers.

Conclusion
Postal strikes in the UK have become a recurring issue, reflecting deeper problems within the postal service and labor relations. For individuals and businesses relying on postal services, it is crucial to stay informed about upcoming strike dates to mitigate disruptions. Customers should plan their postal needs in advance, especially around known strike periods, to avoid delays.

The ongoing disputes highlight the need for a balanced resolution that addresses the concerns of postal workers while ensuring the sustainability of the postal service. As negotiations continue, the hope is that a fair agreement can be reached to prevent further strikes and restore full postal services across the country.