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what if during the great crusade the necrons started to wake up at alarming speed say more than a dozen tomb worlds per day would the imperium be able to defeat with their powerful primarchs and legions of space marines

Do you mean 12 worlds a day for the lenght of the campaign?
That would be 12 worlds x365 days for circa 200 years equalling over 800,000 worlds.

In short no if you go down that route. If the scale was smaller its more probable.

However Cron tech is and was still incredibly powerful. Ia12 has them obliterate a sector in fairly short order.