An altcoin market correction is a very possible scenario.
BTC is in a short term downtrend with decreasing volume. This means there is a lot of indecision in this market and people are waiting to see what will happen.
In the last BTC drop, the price of alts vs BTC did not change much. Since then, they have rallied. Most of them with significant gains, some with 200 or 300% gains. Bitcoin is currently closing in on the tip of a triangle, which will be an important decision point for the altcoin market.
If Bitcoin breaks below this triangle, it will be a point with lots of people taking profits out of alts. If you are in profitable altcoin trades, now is a good time to take another look at them and start thinning out your positions and locking in profits.
If Bitcoin is able to break out of its short term down trend and break above the triangle, you can reevaluate your altcoin positions and look for re-entries. This is a very violent and unpreditable market, and the last thing you want is to be holding bags of shitcoins as they drop heavily in value. It never hurts to take profits.
The altcoins are currently in a mini euphoria phase with BTC teetering on the brink of another large move. You want to be ready for every possible scenario.