Unable to change debit order dates

I was reluctant in writing this but I don't understand why I have to go through a lot of trouble changing just the debit order dates. A quick back story: recently changed jobs and with that the pay date changed as well. I have contacted all my creditors and advised of the changes and to have my debit order dates changed to the last day of the month. Contacting Capitec to change my debit orders has been a nightmare. This new job processes salaries from an overseas account from the 21st of each month and with that being said, payments are paid from anytime between then and the end of the month. There is no specific pay day which is why I want to move everything to the end of the month to be safe. I called capitec to make those arrangements but they requested that I provide proof in the form of a payslip... Seriously, where am I supposed to get a payslip when I have not even gotten paid yet? Why do I have to go through all of this just to change my debit order date? This seems like I am being taken for a ride to delay this change so that all my debit orders bounce and my credit will then be affected negatively.

I do not need to be taken from pillar to post, all i want is to change my debt order dates to the end of the month, that is it!