When you ask it's the right time to buy Ethereum, but for now it would be better to hold the Ethereum you already have. There will be time to buy Ethereum again in the next few months because right now Ethereum is doing well and trying to go higher.
if you already have ethereum clearly keep holding it and wait until ethereum reaches the maximum price level. but if you do not have and want to invest it would not hurt, because it is estimated that ethereum will continue to increase until the end of the year and could be until the next year which will reach its highest point.
as long as you are sure and have enough capital not to be afraid to save it in ehtereum investment. with a fairly good bitcoin movement that will bring all altcoin is no exception ethereum will also increase.