Coach Andy Robinson remains hopeful that Steven Shingler will be allowed to play for Scotland in the future.
An International Rugby Board panel ruled that London Irish's Shingler, 20, can play only for Wales and not for Scotland, having played for Wales Under-20 against France U20 in 2011.
The IRB council meets in May and will discuss whether or not nations should use U20 teams for eligibility.
Robinson said: "We feel we can proceed further in support of the player."
Shingler, who can play fly-half, centre and full-back, has been at the centre of an eligibility row during the Six Nations.
Since finding himself at the centre of the row, the former Scarlets player's elder brother Aaron, 24, made his debut at openside flanker in Wales' 27-13 win over Scotland in February.
Wales objected to Steven Shingler's inclusion in Scotland's tournament squad because he had played for Wales Under-20, the nation's designated "second team".
But in May the IRB will discuss ending nations' right to use Under-20 teams to secure players' full-Test eligibility.
Robinson included the former Scarlet, who has a Scottish-born mother, in his original squad.
But the Welsh Rugby Union successfully argued that having played for Wales Under-20 in a designated eligibility "capture" game against France Under-20 in 2011, Shingler could be eligible only for them.
An initial informal assessment by the IRB determined that the player appeared to be tied to Wales and the SRU formally asked the IRB regulations committee to review the case.
A three-man panel chaired by Peter Boyle, of Ireland, and also including Italy's Giancarlo Dondi and New Zealand's Tim Gresson heard evidence from Shingler, his agent and the Scottish and Welsh unions in Dublin on 27 February.
The IRB regulations committee panel confirmed: "Although Shingler had not signed the union eligibility confirmation form he had been fully advised by the WRU that playing in the France Under-20 v Wales Under-20 match during the 2011 Under-20 Six Nations would capture him for Wales."
However, the panel also pointed out that the full IRB council has the right to overturn the decision and recommended that the issue of players being tied to countries while playing at Under-20 level should be reviewed.
The statement read: "It [the regulations committee panel] also noted the recommendation of the IRB Rugby and Regulations Committees, subsequent to this hearing, that the designation of the Under-20 side as the next senior national representative team should no longer be sustained.
"This issue will be considered by the IRB council at its special meeting on 15 May 2012."
Robinson added: "What we are pleased about is that the Under-20s cannot capture players in the future.
"It looks like one game has captured one player. Obviously because of that we feel we can proceed further in support of the player."
A Scottish Rugby statement read: "Scottish Rugby notes the decision of the IRB Regulations Committee hearing the Steven Shingler eligibility case.
"We remain fully supportive of Steven Shingler, a talented young rugby player who has expressed his sincere and earnest wish to represent Scotland.
"We await the full written decision of the IRB Regulations Committee and may comment further on receipt."