this is so disappointing. I have several websites using Buildr, zen tools and almost all Joomlabamboo extensions - I changed a few years back from Gavick because there extensions were not always compatible with one another and gave me lots of trouble. Buildr has worked perfectly with all extensions and I just love it and cannot understand why you won't upgrade it to meet Joomla 4. Gavicks products are just not as good, I know I used them for years.
To remake my personal websites is a bummer, but doable, but my customers websites...that will cause me so much work and I most likely will not be payed for it as we had "finished" the product/website according to their needs.
I'm not professional enough to switch from Joomlabamboo in a week or two, it will take me much longer because my customer has very specific thoughts of how things should be and I finally got there with JB Buildr.
I´ve payed almost 300 dollars a year and now there's nothing left, I have do it all again, both work and payment. I am so disappointed.