Change billing date of recurring contribution (PayPal payment processor)
Short answer: no, so long as you're using PayPal.

Recurring contributions come in two flavours, depending on your payment processor: token-based with the amount and schedule controlled by CiviCRM, or payment processor controlled. Some payment processors will allow either method.

PayPal is only controlled by the processor, so contrary to what you got as an answer, the only way to change the billing date is via PayPal. But if they tell you you can't, then you can't. In general, PayPal is very donor/customer oriented and it tends to put all the power into the hands of the donor/customer, not you the merchant/organization. So it's not usually the best option for large organizations that are used to managing the recurring contributions themselves. You can check out other options here:

https://wiki.civicrm.org/confluence/display/CRMDOC/Payment+Processors

Note that even if you're using a payment-processsor-controlled recurring schedule, there may be an API that lets you change the schedule indirectly via CiviCRM.