Thanks you Paul. This isn't me 'dodging' buying the correct parts I should add. I fully intend to carry on using Teensy's in my projects when (if) my income resumes.
I designed a pcb a while back (my first ever) and had it made, totally without thinking really. That uses the processor and the bootloader. No idea why I didn't twig that I needed a programmed bootloader. So the board is sitting there unable to be finished.
Pretty sure I can lift it off carefully with my SMD heat gun and the mini nozzle I made for it. The project I intend to remove it from has a standard 3.2 in it, so if I mess it up, at least I can simply plug a new programmed 3.2 into the breadboard IC holder.
In future, I'll know that I need pre-programmed bootloader ICs.
As a side note, I split my last smd components order between RS in the UK and Digikey in the US. Digikey was FAR superior. I am UK based.
The parts were mostly cheaper and available in smaller quantities from Digikey (not everyone needs a minimum order of 20 bespoke slideswitches Mr RS), and turned up in one package, and within 3 days. No parts missing and just over £34 in total.
RS on the other hand...
Order arrived literally individual item by item, spread over 2 weeks. Some days, a jiffy bag arrived with one pack of 25 0805 resistors in it. I think in total, I had 16 packages for a £35 order. None of the parts said they were outside the UK when ordered, but it turned out that several did end up coming from the US.
Then some items turned up twice. Total mess.
Not to mention that even though I paid the full sum at checkout, they took the individual amounts out of my bank account as they posted them. I had an entire page on my bank statement dedicated to a £35 RS order.
Will never use them again.
Thank you for the advice Paul