When to start taper off pre holiday

Hello, I'm very new to bird feeding so please excuse the silly question Slight smileMy feeder is currently visited daily by a robin and a very large flock of sparrows (about 40-50 of them!). In 2 months time I will leave on holiday for a few weeks and no neighbors can help refilling the feeder.

I think I'm supposed to taper off the feeder off gradually before leaving so birds stop visiting, but how far ahead do I have to do this? Can I continue to feed the birds until November and then start tapering?