You don't really need to re-surface it. You need to remove the oil shine.
BUT since it's been 3 months, it's probably absorbed a bunch of oil, Suprised you have not seen any reduction in performance. As such, I'd suggest a deep cleaning using some very strong deep cleaner, like Clean and Dull.
If you wish to refresh the surface, since it's 500/4000 grit surface, take a 500 grit Abralon pad to it, then follow-up with a 4000 grit pad. If it were in need of a true resurfacing, you mght want to start with a 360 grit pad, then the 500 grit pad, then the 4000 grit pad.
Normally after 3 months of usage I'd suggest sanding it to 500 grit with an Abralon pad, putting it thru a Revivior oven at your local pro shop (to do a thorough oil removal), and then sanding it with a 4000 grit Abralon pad to restore the original surface. Since you said you noticed no loss in performance, I'd guess this process is not necessary.
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"None are so blind as those who will not see."
