Is it normal to feel a line of stitches from front of ear down neck 3.5 years post neck lift?

it could be that your surgeon used permanent sutures, in which case yes, you will always be able to feel them forever.

Hello,
Thank you for your question.
It’s not uncommon to feel a line or band of firmness or altered sensation along the incision site even years after a neck lift, as scar tissue and nerve regeneration can cause this feeling. Although the stitches themselves dissolve or are removed much earlier, the underlying scar may remain palpable for an extended period. If the area is not painful, inflamed, or showing other signs of complications, this is generally normal. However, if the sensation worsens or is bothersome, a follow-up with your surgeon for evaluation and possible scar management treatments may be helpful.

Providing that sutures on SMAS flap were done with permanent suture material (proline, naylon) it is possible that you can still palpate them under thin skin. Hope this helps.