Unfortunately your online degree will remain unaccredited.  You would need to be enrolled and earn your degree after the school was officially accredited to earn that title, but you may still benefit from your schools new found accreditation.

While many prospective employers care about the accreditation title, they are less interested in when that accreditation date came to pass.  The odds of you getting grilled for the precise date of your online degree vs. the accreditation date are slim to none.  Besides, most believe if the school was on the path to becoming accredited while you were there that it’s basically one and the same.

Still, if you get grief for your unaccredited degree at a now accredited institution you can enroll in a “replacement” degree program, whereby you can take just a few classes to earn your accredited degree title.