Yes that's possible and there's an official communication to all the card holders too.
I posted about it some time back - https://www.technofino.in/community/threads/sbi-cards-potential-spam-mail-regarding-reward-points.3153/
HDFC approved my request and it is reflecting in net banking portal. However, it's only a 51k jump.
So even after this enhancement, my Kotak Zen has almost double the limit of HDFC Regalia.