Nope! You can set up as many auto-investments as you like. As long as you have enough money in your account, they’ll be placed in the timeframes you set.
If you want to have multiple running at once, we recommend making them the same date (e.g all on the 1st of the month). Then, you can set up an automatic payment to ensure you have enough money in your account to cover them all. It’s no biggie though, if you don’t have enough money, that order just skips and your next one will be placed as usual.