Lock in period for selling property wherein capital gain was reinvested

1. As per sec 54 exemption can be claimed from investments made in a new residential property if the purchase is made within 2 years or in case of construction within a period of 3 years. 
2. However, the above exemption shall be nullified if the same residential property is sold within a period of 3 years from the date of investments. The cost will be taken as nil if the entire investment is claimed as exemption u/s 54. 
3. In your case, if the residential property is sold within a period 3 years from the date sale that is within July 2020, then if the entire amount claimed earlier will be deducted from the cost of acquisition. 
Please correct me if the above solution has an alternative view. 

Lock in period is 3 years u/s 54