When this latest batch of low temps hit last week I relised not going to get all mine done in December so Saturday morning spend an hour hand delivering a simple "sorry no clean in December note" to about 60 houses all in same area.
Spoke to a few customers who understood no problem and even got a tenner tip off an old bloke who is normally a right PIA

Result is I felt a little better as now got less pressure to get them all done ... ok loss of income but they were never going to get done anyways

..... plus stops any moaners in January.
Maybe a little ott but sometimes pays to go the extra bit.