For the purpose of detemining the period of holding , the date of acquisition and the preceding date of transfer is considered. Therefore STCG
However if FLAT is purchased from co-operative housing society then the date of allotment of shares shall be considered for determining the peiod
Plus consider Mr. Praveens point also for PGBP if appplicable
For saving tax
IF YOU HOLD IT FOR ATLEAST 36 MONTHS THEN YOU WILL BE ELIGIBLE FOR OTHER EXEMPTIONS ALSO LIKE
sec 54 In case of residential house property
Applicable only to HUF/ individual
RESIDENTIAL HOUSE PROPERY IS TRANSFERRED (if you declare the asset as house proprty)
sec 54 F (other than residential property)
sec 54 EC (LTCG Only)
As mentioned by Mr. Praveen NHAI or RECL (REDEEMABLE AFTER 3 YEARS)
Max amount 50 lakhs rupees
invest within 6 months from date of transfer
You should hold the property