I’ve never noticed any effect after not having it for several months and I drink black tea as dark as possible (just short of using multiple teabags in a cup xD). Do you really notice that you’re more awake, like beyond placebo?

I didn’t know it had caffeine until recently, so I think I just never got the placebo effect of “this should keep me awake” and apparently the residual effect, at least on me, is unnoticably small. When I learned, I avoided it for a while during the evening (even though I didn’t remember any effect, I wondered if maybe I sleep worse and just didn’t know to attribute it?), but I’ve since tried it out and there’s really no difference even if I drink it straight before going to sleep