No, this HF has nothing to do with the POS. There is no certain date for ETH 2.0, just rumors that it will start in Jan 2020. It is not clear whether a full POS will be introduced, or mixed POS/POW at first for better security. Full POS may happen still in Q1 2020 if there are no bugs.
But what is means this hardfork on 7th December 2019? Which changes twil they have have?
January may be will be even better time for POS. The close to BTC halving - the better...
I hope that you will not be a lazy person to read more through use the external source from the internet
EIP-152: creates the prerequisite to test the Equihash PoW within the framework of an Ethereum contract. This enables relay and Atomic Swap transactions with Zcash (ZEC).
EIP-1108: makes zk-SNARKs cheaper, so that more cost-effective scaling and data protection applications can be created.
EIP-1344: adds ChainID opcode for contracts to track the correct chain on state channels and plasma.
EIP-1884: prevents spamming attacks by changing the cost of some EVM opcodes.
EIP-2028: Makes zk-SNARKs and zk-STARKs cheaper by reducing the gas cost of accessing data within a transaction.
EIP-2200: changes the EVM cost calculation (adjustment of SSTORE gas costs taking into account SLOAD gas cost change).
Source :
https://medium.com/ethereum-cat-herders/istanbul-testnets-are-coming-53973bcea7dfThis is the first part of the Istanbul upgrade, the next part (2nd) will be going on next year.