The first is, of course, shutting down the lab side of my business. There's kit to sell (some sold already) materiel to dispose of and a need to do some manufacturing for one customer, some custom work for another before it all goes. And a butt-load of paperwork to sort, file, recycle etc.
Then there's my development job. It's very different in a way, from so many things I've done, yet at the same time draws on physical chemistry, engineering and instrumentation experience as well as development process experience. Love it, get a little frustrated by it, wish I were doing it full time (2 days/week isn't anything like enough to acheive what's needed in the time frame) and really glad to be onboard.
Finally job number 3, managing the main shared lab facility. Again there's not enough time, though in a few weeks that will be less of a problem. The biggest frustrations are a mix of IT (because everything is done in the cloud, it's all remotely managed and I can't 'just' fix it now & work) and trying to sort out someone else's quality system. Even though I respect and appreciate the originator of that system very much, it had them working hours into the night and is hugely labyrinthine and deeply customised, and at the same time basic good practices weren't always followed (like marking obsolete documents as such when issuing updates). And there's no 'logic' to the system that allows one to locate all temperature monitoring documents in a single subsection etc.
So I went and made a coffee, having had a less-than-efficient morning trying to print a copy of a record document and top up liquid nitrogen containers. The window to the kitchen was open the out-door scent coming in was fresh and cool. It's not all bad then. :-)