It's early days意思是“为时尚早，言之过早，来日方长”。

【例句】
While they say it is early days, there is nothing theoretically different about applying the same process to humans.
虽然他们强调现在形成定论还为时尚早，但理论上而言将此过程应用于人类并无不妥。

So in short, it is early days and I need a bit more time to make all these plans concrete.
因此，简而言之，现在还为时尚早，而我需要多点时间去让充实所有这些计划。