I will not be having a CT call any time soon...
BUT I wanted to offer some suggestions.
Often, designers who are looking to replace 1 or 2 team members will simply invite someone to their team, not have a huge call where they have to disappoint a bunch of people. It's not easy for anyone to go through that.
My suggestion would be to remain active in the forums and when you post layouts in the gallery, add it to the designer's inspiration gallery also (listed by the name of the designer whose products you're using) so they will be sure to notice your pages. You want to be on their radar!
I think Adi's comment about CT'ing being a nice way to try out that designer's offerings is understandable... I remember when I first got involved here being so 'hungry' for new kits but due to my budget I felt safer sticking to the designers I KNEW I would use their stuff (and use over & over!). It is nice to try out other designers without having to 'risk' spending on money on something you might not like... BUT. That's kind of what store collabs are for? And freebies. At least from my experience as a designer, if I'm out there looking for someone to ask to be on my CT, I usually look to people who already use my designs, are a regular to semiegular customer (because those often are the ladies that stay faithful and active on my team) and I *know* can rock what I make.
Hope this helps!!!