After going all suggestions/reading threads, here is the summarized version of what i found:
There are 3 Axis Websites for buying gift vouchers/book tickets & earn rewards - 1st is Grab deals (only for festive offers & specific vouchers & capping on rewards & BP credit in 90-120D 2nd is Gift Edge (always gives bonus points and for every voucher and no cap on rewards & credit in 30-120 D). 3rd is Travel edge.
Now, on Grab deals portal-Max. 10000 points can be earned on per customer per month. EDGE REWARD Points (Accelerated Rewards) will be posted within 120 days from the date of transaction on Grab deals.
On Gift Edge portal- There is no capping to any EDGE REWARD Points that you earn but in case of Flipkart (5x)/ Amazon (3x) (its limit is 10k purchase per month for Flipkart & Amazon PV & 50K for ASV & 20K for Tata Cliq). You either get 10X or 5X EDGE REWARD Points depending upon the brand you chose. 10X EDGE REWARD Points can be earned on 100+ Brands with zero capping. 5X EDGE REWARD Points can be earned on multiple Brands such as Flipkart, Croma, Mobile Recharge, Big Bazaar, More, Spencer's Retail, Uber, Ola, Grofers etc. with zero capping.
On Travel edge portal- No cap on Travel Edge reward points.