Hello Darshan,
The answer is probably yes. But you won't be able to apply for those Olympiads which are available till 12. But you can apply for those Olympiads which have 12 passed or open to all as their eligibility criteria. But you ain't be able to sit for the Olympiads which have undergraduate or till 12 as their criteria for you've passed 12 while you've taken a drop.
Hope this helps.
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