All requirements to attend appointments at the Jobcentre in person were suspended for at least 3 months, starting from Thursday 19 March 2020. Jobcentres remain open, but mostly only for the most vulnerable claimants, such as homeless people, and by appointment only. No-one will be expected to attend a Job Centre unless specifically requested to do so. 
The DWP is trialing the use of video appointments. 

Advance Payments can be awarded without the need to attend the JobCentre and New Claim Interviews and ID Interviews will be conducted over the phone.

The message from DWP is 'don't call us, we'll call you' unless your need is urgent.

After making a claim, the claimant will receive a call from a UC adviser to help complete their claim / verify ID.

This will be from a withheld number - so claimants must make sure they've not blocked withheld numbers, and answer that call.