Start off every season I drop the oil. General service. Starting and running through the winter ( even up to temp ) is nowhere near the same a riding,does the oil no good.
I do run and use it when possible ( without lockdown ) during winter, so doing it by the manual would not work for me.And, In the Suzuki owners manual, it states something like for winter storage, to FILL the crankcase up to the filler hole with oil. Then drain it down before running it in Spring....