I try to spread the money around... I've bought from quite a lot of sellers in 2021. Exotic Blanks, of course, but also WoodTurningz, Woodcraft, Rockler, PSI, Bear Tooth Woods, PeachTree, WoodPenPro, Timberbits, Crooked Mill, The Wood Turning Store, and others... I've found PSI & Rockler in particular, seem to be slower on the "we actually shipped it" front. I don't know why, given their size, maybe it is simply BECAUSE of their size, they may just get more orders as they are known by everyone? Had some slower shipping times from WoodPenPro, however I believe he is in Hawaii, and the whole pacific shipping debacle most likely caused the slowness there.
I have also bought from sellers here on IAP and on Etsy, Ebay. A lot of these companies are run by individuals are families, and sometimes this is not the only thing they do, they often have other jobs. I know some sellers I've bought from have actually stated on their Etsy store pages or in other copy that they ship only on specific days (i.e. Monday and Thursday, for example). I don't have customers breathing down my neck for pens, and the few who have actually ordered pens from me have ordered well in advance of when they needed them, which made it easy on me.
I pretty much order with the assumption "It will get here when it gets here" these days. My primary goal is to just make pens, put em up on a store, and let 'em sell. Because I have a day job, I may in fact have to have a "I ship Mondays and Thursdays" policy myself, when the time comes, as I don't know if I'll be able to ship every day of the week.
Its a crappy world out there for anyone shipping anything... I was just at the post office today asking about the most cost effective way to ship small things like pens. The cheapest options were the flat rate boxes and envelopes, which bottom out at $8.45 and $7.94. Would be so nice if there were little 2"x2"x8" padded boxes for $3.95 each that we could ship our pens in.

Its a terrible environment for anyone who has to ship these days...