Unite members will not undertake any overtime, will refuse to work any additional hours or do work not proper to their role in the organisation.
They will also refuse to travel outside of their working time, nor will they work in a location other than their normal place of employment.
This is an important day for Unite members in the Post Office.
They are keen to impress upon their employer their dissatisfaction with the failure to reach a pay agreement with the union and see this an opportunity to protest.
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Scotland Yard said the male youths will appear in custody at Westminster Magistrates' Court on Saturday.
Windy this weekend with gales across northwestern parts of the UK. Rain spreading southeast.
Greater Manchester Police said "inquiries are ongoing to fully understand the circumstances of the incident."