The phrase "additional instructions are" is correct and usable in written English.
You can use it when you want to indicate that there are more instructions to follow or that further details will be provided.
Example: "Please note that additional instructions are included at the end of this document for your reference."
Alternatives: "further instructions are" or "supplementary instructions are".
The subjects were instructed that, when using Pseudo-Joystick control they should occasionally look back to check the robot's position; these additional instructions were necessary since early tests had shown that without glancing back it was almost impossible to avoid obstacles.
On 24 November 1914, as the first line battalions began to go overseas, additional instructions were issued allowing the raising of a third line battalion once the first line battalion was on foreign service.
Information and additional instructions were also provided to the other study sites in a preventive manner.
If there were less than 33% or more than 66% correct Stops at the medium SSD in a given block, additional instructions were given to slow down or speed up responses, respectively.
Additional instructions were then given, that half of the statements would be semantically intact (such that their meaning could be understood) and the remaining half would be scrambled (such that the order of the words would be mixed up and, thus, the propositional meaning obscured).
This avoids over-tracing down the center of the dendrite (additional instruction is in the manual).
Apparently no additional instruction was given regarding consideration of the manner or nature of the witnesses' testimony or of the witnesses' possible motivations to speak falsely.
No additional instruction was given.
Subjective meditation experiences were monitored by the TM instructor via self-reports and additional instruction was provided when necessary.
However, additional instructions have been inserted in SSRLocator's code.
