The subscriber we tested during the UAT session didn't have trail (24282815) and we had the following Time Excution on OLD and NAW :

changeSubscriberNo 0,92s 1,62s

But with subscriber with Trail (24220910), we are getting the following :

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ser="http://server.api.nep.mobinets.com/">
<soapenv:Header/>
<soapenv:Body>
<ser:changeSubscriberNo>
<!-Optional:->
<oldSubscriberNo>24220910</oldSubscriberNo>
<!-Optional:->
<newSubscriberNo>24282819</newSubscriberNo>
</ser:changeSubscriberNo>
</soapenv:Body>
</soapenv:Envelope>

OLD: 0.95s
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
<soap:Body>
<ns2:changeSubscriberNoResponse xmlns:ns2="http://server.api.nep.mobinets.com/">
<return>
<responseCode>0</responseCode>
<responseMessage>SUCCESS</responseMessage>
</return>
</ns2:changeSubscriberNoResponse>
</soap:Body>
</soap:Envelope>

NEW : Few minutes before the following error on New
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
<soap:Body>
<ns2:changeSubscriberNoResponse xmlns:ns2="http://server.api.nep.mobinets.com/">
<return>
<responseCode>1</responseCode>
<responseMessage>general.exception.error.updatingError while deleting trail GPON For subscriber : 24220910 :Error unmarshaling return; nested exception is:
java.io.InvalidClassException: org.springframework.web.client.HttpServerErrorException$InternalServerError; local class incompatible: stream classdesc serialVersionUID = -3578438846357869624, local class serialVersionUID = -3839068165753821818</responseMessage>
</return>
</ns2:changeSubscriberNoResponse>
</soap:Body>
</soap:Envelope>