This is interesting cause i have several books saying the troops started to land only at evening of 22nd and that operation was completed by the early morning of 23rd Given that the order to go ahead was given on 22nd i would be quite surprised if Finns landed there on 21st However none of this matters Agreement quite clearly states that if the war came to Baltic Sea then Finns were allowed to place troops to the island And what do you know Nazi Germany was at war and used Baltic sea making it legal under the demilitarization treaty for the Finns move troops there technically they could have kept troops there the whole time its not Finnish problem if SU ca nt understand treaty texts Also there is no requirement for the Finland to participate into that war in order to allowed to place troops in land Also as it happened Soviet aircraft attacked unsuccessfully the ships headed to land before they got there that is on 22nd of June