My understanding is that banks close on a weekday at 4.30 -5pm depending on location and bank. My issue is that I had a phone call from the direct local branch go my bank at about 6pm. Do they still work after hours?
Yes, a lot of processing gets done after the bank closes to the public.
It's far less common though for branches to make calls to query things- most of the work is done in processing and customer service centres.
Could it have been a scam call?
Someone claiming to be from my business bank rang me. They then asked for my account number and sort code. I refused to give it. They told me it was to verify who I was. I replied if you have phoned me from my bank you will know my account number. This was a scam. I reported it to my nearest branch and they confirmed there were other instances.