Facelift and discoloration. I use 4% hydroquinone AM and PM. Is this normal and how long before dissipates?

There are many reasons to have redness to your scar and this is typically in patients who have redness to their skin tone and can take up to a year to fade without additional treatment. The redness can be addressed in a number of ways and lasers are usually the most effective. It is best for you to see a plastic surgeon to discuss your treatment options. 

Hydroquinone
is not usually used for redness, it is used for pigmentation. There are a lot
of issues that could cause the redness, but this should be determined by your
doctor. It could be rosacea, broken capillaries, which is hard to determine without
an examination.It is best for you to
see a Board Certified Plastic Surgeon to discuss your options.

Discoloration after a facelift can be due to injury to the skin from the dissection, bleeding that stains the skin, or small telangiectasias that develop.  Hydroquinone is a good option to start, but if it has no results, you may try a peel or laser. First the cause of this discoloration needs to be determined.