Get last accepted solution

darrenSP  You can get the solution accepted time as nested in solution_data but you can not use nested parameter in order by.  
Here you can use a workaround.   Use below approach

<#assign accepted_solution = rest("2.0","/search?q=" + "SELECT solution_data,is_solution FROM messages WHERE is_solution = true"?url).data.items[0] />

<#assign time = accepted_solution.solution_data.time?long />
<#assign latest_soution_id = accepted_solution.solution_data.message_id />

<#assign solutions_count = rest("2.0","/search?q=" + "SELECT count(*) FROM messages WHERE is_solution = true"?url).data.count />
<#assign solutions = rest("2.0","/search?q=" + "SELECT solution_data,is_solution FROM messages WHERE is_solution = true limit ${solutions_count}"?url).data.items />

<#list solutions as solution>
 <#if solution.solution_data.time?long &gt; time >
 <#assign time = solution.solution_data.time?long />
 <#assign latest_soution_id = solution.solution_data.message_id />
 </#if>
</#list>
${latest_soution_id}

 Hope it would work for you.