To be fair to the club, it's a little out of their hands.
The past few seasons, it's been an unknown as to what league we could be in until quite late in the season. This may well have resulted in issues regarding sponsors and even kit suppliers. I'm sure EB Charging initially mentioned a 3-year deal, and like Amazing Thailand decided to pull out.
Any sponsorship deal will depend on the league we are in, and this will determine the price paid and also whether there is interest from other parties. (I can imagine a championship club will find it far easier to attract sponsors).
So only once the club were definitely staying in league 1 could decisions be made by all parties. (sponsors, potential new sponsors waiting in the wings and kit suppliers).
Only when all deals are in place can production begin, initially with pre-production samples. The kit supplier will then need to find space in their production facilities, and source materials before producing the garments. And then get everything boxed up and in all likelihood, put on a slow boat from China.
I know it sounds a faff, but this is the real world of manufacturing.