It doesn’t matter that its 10 seconds, 8 seconds or 6 seconds worth, it’s the build-up of un-burnt fuel without ignition that is the cause for concern.
Fine detail aside, initial Ng acceleration results in a rise in metered HP fuel to the flow divider, which when unseated, schedules metered fuel to the primary and secondary fuel nozzle manifolds (as a function of primary manifold pressure) via separate spring loaded valve ports.
As the twin igniters are positioned adjacent to Primary and not Secondary nozzles, and that the Secondary nozzle valve port opens at a higher pressure than for Primary nozzles, were the Secondary valve to open before the Primary, increased fuel flow would enter the combustion chamber away from the igniters, thereby increasing the likelihood of a hot start, which would explains why many engine types have this 10 second limitation for indication of a light-up.
Both valves ports should be open with all nozzles flowing by around 35% Ng, and as I recall, close to idle speed is achievable with just min fuel flow (i.e. before compressor discharge air influences P3 bellow/fuel valve positioning).
Noting your 212 days, there is no HP fuel flow without Ng rotation, so initially no fuel pressure to open up and surge through the flow divider. Additional metered fuel flow in excess of min fuel flow settings is a function of P3, and as P3 is directly proportional to Ng speed, setting the condition levers to idle or even flight before engine start will not result in a hot start, as there is no input reference to increase fuel flow to the flow divider much before idle speed is obtained. (PPRuNer’s - Please do not try and disprove this theory at home
).