Legal Question in Real Estate Law in California

Only if you have filed a substitution of attorney firing the attorney and replacing them with yourself in pro per.

Yes, after the attorney has either subituted out or has been relieved by court order.

I don't read the law so restrictively as the previous attorneys have. At any time after a notice of pendency of action has been recorded, the notice may be withdrawn by recording a notice of withdrawal in the office of the recorder in which the notice of pendency of action was recorded, the notice must be executed by the party who recorded the lis pendens or by that party's successor in interest, and the notice must be acknowledged. (Meaning notarized.)

See Code of Civil Procedure section 405.50. Nothing in that section requires substitution of attorney or court supervision.

Mr. Roach is correct about the code, however most county recorders do not accept lis pendens documents, whether initial or withdrawals, that have not been filed with the court first, and most court clerks will (correctly) refuse to file documents submitted directly by parties who have attorneys of record.