[Python] How to identify nth row that satisfies condition

I have a dataframe with months and sales. If somebody does 250 sales for 3 consecutive months, they get a bonus.

1. Once the bonus month is identified, the counter resets and starts to count the next 3 consecutive months with 250
2. if there is less than 250 sales, then the counter resets

Month sales 3 month consistency
Month 1 250
Month 2 250
Month 3 250 1
Month 4 250
Month 5 250
Month 6 250 1
Month 7 0
Month 8 250
Month 9 250
Month 10 250 1
Month 11 250
Month 12 250
Month 13 0
Month 14 250
Month 15 250
Month 16 250 1

I want to populate the 3 month consistency column

Tried using cum count with conditions but it did not work and I could not find such an example anywhere. What I tried was to use rolling window to identify every 3rd consecutive record with 250. But then it does not reset after the each set of 3 consecutive 250s.

df.groupby('id').apply(lambda x: x['gt_250'].rolling(min_periods=1, window=3).sum())
#-- grouped by id because this has to be computed for each salesperson_id


The result I got from it was,

Month sales 3 month consistency
Month 1 250
Month 2 250
Month 3 250 3
Month 4 250 3
Month 5 250 3

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