Burnham PVG6 (US Boiler) - Throwing Error 63

I'm looking for some guidance on an issue I'm having with my 8-year-old Burnham PVG6 Hot Water Boiler. The boiler starts and runs for a min or so then clicks off and on several times (Burner flames go out/on, out/on and etc.) ultimately going into recycle/retry mode (STA10) and it repeats until it goes into a "Temporary Lockout" (Error 63). If cycle power to the boiler, it starts working again but ultimately gets the Error 63. This is a hydronic forced air system, and the air is not staying warm/hot so the air handlers keep running because the thermostats never hit the set temp. I've already checked all the electrical connections, blew out the gas line and replaced the pilot assembly. I'm reading that the control boards are known to go bad after several years so that is my next step before calling the plumber who did the install. Parts only have a 1-year warranty so no luck there. Has anyone experienced such an issue before? Thanks.