"[...] ran through til around midnight when it shut down for the night"
BBC schedules in July 1953 usually opened with children's programmes at 17:00 - although sometimes in mid-afternoon with a film or live sport.
There was a break between the end of the children's programmes at 17:35 or 18:00 - restarting again about 19:30 to 20:00. Apparently so it didn't provide the temptation for people to miss going to Evensong at their church.
It closed down about 22:40 with an audio only news update. On Sunday the final programme was "The Epilogue" - usually a cleric droning on in the style of Radio 4's "Thought For The Day".
There were no other TV channels.