any reason why wallets are locked on Bittrex ? Just regular maintenance ?
And will the price go down when they unlocked them ?
And will the price go down when they unlocked them ?
Update about the issues in different exchanges (statement from the official Discord):
The Sia team has been actively working to fix some of the underlying issues that have recently affected the exchanges. They are working on new algorithms for rebroadcasting transactions on the blockchain (PR #2611, #2599, #2598), have added an API endpoint for confirmed transactions (PR #2614), and have added new regression tests for the wallets transaction output (PR #2608, #2601). The team is well aware of the exchange issues and these improvements are in support of a long-term fix, rather than a band-aid. You can follow the development progress on GitHub, or stay up to date via reddit at https://www.reddit.com/r/siacoin/comments/7ld1ic/siacoin_exchange_issues_megathread/.
is there a reason that the course is so high now? 
it's up to the upcoming hardfork
it's up to the upcoming hardfork
Please remind the hardfork on block 139.000 (in about 19 days) will not generate a second coin (no "airdrop"). This fork will be non-contentious, it is just a protocol upgrade aimed to correct a bug in the mining difficulty. All the infrastructure (mining pools, exchanges, services) and users are upgrading to version 1.3.1, so the legacy blockchain will be abandoned.
If you have coins already on an exchange there is nothing to do, as they have already upgraded. If you hold your coins in the Sia-UI client just be sure it is updated to version 1.3.1. Even if it is in an outdated client or in cold storage you'll still keep your coins as long as you keep your recovery seed: at any time in the future you just have to install an updated client and use your seed to access your funds