...until I get used to this community.

...until I become accustomed to this site.

...until I am familiar with this site.

My First Day of italki.com

Could you correct my first note?

Hi italki,

I've just signed up here in italki today. Contrary to my expectations, as many as more than 50 PMs have arrived in my box in first 6 hours, so I couldn't reply to any of them. I should apologize to those who want to be a real language partner and am sorry that I'll not respond to any PM for a while until getting acclimatized to this community.

Best Regards,
Miho

My First Day of italki.com

Could you correct my first note?

Hi italki,

I've just signed up here in italki today. On the contrary, I have recieved as many 50 PMs today for the first 6 hours, therefore I hardly able to send replies. I should apologize to those who volunteered to be my language partner and I'm truly sorry for not able respond to any PM for the meantime until I get accustomed to this community.

Best Regards,
Miho

My First Day of italki.com

Could you correct my first note?

Hi italki,

I've just signed up on/to here in italki today. Contrary to my expectations*, as many as* / more than* 50 PMs have arrived in my box in the first 6 hours, so I couldn't reply to any of them. I should apologize to those who want to be a real language partner, and I'm sorry that I'll I cannot reply/respond to any PM for a while, *until getting acclimatized to this community.

Best Regards,
Miho

*unexpectedly

*as many as 50   <em>or</em>   more than 50

*while/until I become accustomed to/familiar with  this community

My First Day of italki.com

Could you correct my first note?

Hi italki,

I've just signed up for italki today. Contrary to my expectations, as many as 50 PMs have arrived in my box in the first 6 hours, so I couldn't reply to any of them. I should apologize to those who want to be a real language partner and am sorry that I won't respond to any PM for a while until getting acclimatized to this community.

Best Regards,
Miho