On the recent teleconference of the key developers of Еthereum decided to abandon the implementation in the network code update ProgPoW, which could lead to reduced efficiency of ASIC miners.
The developers felt that the update requires a serious audit, confirming its real possibilities, and would like to have more about it in cryptosuite. This process presumably could be delayed until March or beginning of April.
Recall that activation in a network hard forks Constantinople to be held on February 27 at the block 7280000. The last time its implementation was prevented by a vulnerability in the update EIP-1283, which has not been sufficiently explored by the developers.