Keep holding is the most bad strategy for this time after holding them in a couple of months the price of altcoins get dump if the price of it get highing so its hard to predict what will gonna happened. If yoy are gonna hold altcoins for long term.
This is a subjective approach and different people would have different opinions. In case you have Bitcoin, you should HODL on for some time to make sure you have some good profit margin to cash out. The reason I prefer to HODL right now is purely because of the volatile market and the profits that could be made. IN case you have some coins which are too slow to gain weight, better switch to Bitcoin.