Loose leaf rate of degradation when opened?
I'm a slow tea drinker and people often gift me loose leaf teas--some vacuum packed and some not, usually varieties jasmine green tea and oolong tea from Hong Kong and Taiwan.
I don't expect loose leaf teas to ever go bad, but I am hesitant to try more than 1-2 varieties at a time because it could take at least a few months to go through a pack (part of that is I use less leaves because often just want the flavor of tea to replace water). If I try more varieties, opened pack might take a year or more to finish.
Can someone describe what to expect with regards to the rate of degradation in quality? For example, in the coffee world, coffee grounds don't last long and grinding beans from fresh is a necessity for a quality cup. Coffee beans not vacuum packed and opened should ideally be consumed within 2 weeks (up to a month in some rare circumstances depending on the beans).
I expect teas to last way longer than that since it's less oily and probably drier. Old beans might taste off, but old tea leaves might be fainter in flavor? Avid loose leaf tea drinkers--is this ever a consideration and do you do more than to just open a packs and store them normally or try to prevent such degradation by vacuum-packing, freezing, etc.?
P.S. On an somewhat-related note--if you were to re-use tea leaves after steeping, would it make any difference whether you re-steep immediately after while the tea leaves are still hot or could you get better results allowing it to cool down?